Combination of an angiotensin-II antagonising benzimidazole with manidipine for the treatment of hypertension

Abstract: This invention relates to a pharmaceutical composition for angiotensin II-mediated diseases, which comprises a compound having angiotensin II antagonistic activity of the formula wherein R¹ is H or an optionally substituted hydrocarbon residue; R² is an optionally esterified carboxyl group; R³ is a group capable of forming an anion or a group convertible thereinto; X is a covalent bond between the 2 phenyl rings or a spacer having a chain length of 1 to 2 atoms as the linear moiety between the adjoining phenylene group and phenyl group; n is 1 or 2; the ring A is a benzene ring having 1 or 2 optional substituents in addition to R²; and Y is a bond, -O-, -S(O)m- (wherein m is 0, 1 or 2) or -N(R⁴)-(wherein R⁴ is H or an optionally substituted alkyl group), or a pharmaceutically acceptable salt thereof in combination with a compound having diuretic activity or a compound having calcium antagonistic activity.

Description: Field of the invention This invention relates to a pharmaceutical composition for the treatment of hypertension which comprises a compound having angiotensin II antagonistic activity or a salt thereof in combination with a compound having calcium antagonistic activity, and to a method of its use. Background of the invention While calcium antagonists have been used as therapeutic agents of circulatory diseases such as hypertension, cardiac diseases, cerebral apoplexy, nephritis and arteriosclerosis, it has also been known that they tend to cause such undesirable side effects as tachycardia, hypotension, erythroprosopalgia and encephalagia, which are considered to be due to their abrupt vasodilative action. On the other hand, it is disclosed in EP-0425921, EP-0459136 and EP-0520423 that benzimidazole derivatives have angiotensin II antagonistic activities and are useful for the therapy of circulatory diseases including hypertension, cardiac diseases (cardiac insufficiency, myocardial infarction, etc.), cerebral apoplexy, nephritis and arteriosclerosis. The mechanism of the action is considered that the benzimidazole derivatives inhibit the binding of angiotensin II having a strong vasoconstrictive action to an angiotensin II acceptor. In EP-A-0 400 835 and JPA H5(1993)-132467, it is disclosed that an imidazole derivative having angiotensin II antagonistic action is administered together with a diuretic agent or a calcium antagonistic agent. Obiect of the invention The invention is intended, by combination of a compound having angiotensin II antagonistic action or a salt thereof with a compound having calcium antagonistic activity, to perform especially remarkable effects, to reduce undesirable side effects and to cover up defects observed in administration of a medicine consisting of a single component. Summary of the invention Circumstances being such as above, the present inventors have made extensive and intensive studies on the effects of co-use of a benzimidazole derivative having angiotensin antagonistic activity with a compound having calcium antagonistic activity, and, as a result, they have found that the co-use performs especially remarkable effects which were not observed in the administration of the respective compounds singly, thus accomplishing the present invention. More specifically, the present invention relates to (1) the use of a combination of (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a pharmaceutically acceptable salt thereof with manidipine hydrochloride for the manufacture of a medicament for the prophylactic or therapeutic treatment of hypertension and (2) a pharmaceutical composition for the treatment of hypertension, which comprises (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a pharmaceutically acceptable salt thereof in combination with manidipine hydrochloride. Detailed description of the invention The benzimidazole derivative having angiotension antagonistic activity to be used for the pharmaceutical composition of this invention is (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate. As the salt thereof, pharmaceutically acceptable salts are used, e.g., a salt with an inorganic base, organic base, inorganic acid, organic acid, or basic or acidic amino acid. Inorganic bases appropriate to form the salt include alkali metals such as sodium or potassium, alkali earth metals such as calcium and magnesium or aluminum, and ammonia. Organic bases appropriate to form the salt include trimethylamine, triethylamine, pyridine, picoline, ethanolamine, diethanolamine, triethanolamine, dicyclohexylamine, and N,N'-dibenzylethylenediamine. Inorganic acids appropriate to form the salt include hydrochloric acid, hydroboric acid, nitric acid, sulfuric acid, and phosphoric acid. Organic acids appropriate to form the salt include formic acid, acetic acid, trifluoroacetic acid, fumaric acid, oxalic acid, tartaric acid, maleic acid, citric acid, succinic acid, malic acid, methanesulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid. Basic amino acids to form the salt include arginine, lysine and ornithine. Acidic amino acids to form the salt include aspartic acid and glutamic acid. As compound having calcium antagonistic activity manidipine hydrochloride is used. The angiotensin II mediated disease is hypertension. The pharmaceutical composition of the present invention can be administered orally or non-orally in the form of, for example, granules, powders, tablets, capsules, syrup, suppositories, injections, emulsions, elixir, suspensions or solutions, by mixing these effective components, individually or simultaneously, with pharmaceutically acceptable carriers, excipients, binders, diluents or the like. In the case of formulating the effective components individually, while thus individually formulated agents can be administered in the form of their mixture prepared by using, for example, a diluent when administered, the individually formulated agents can also be administered separately or simultaneously or with time intervals to the one and same subject. The pharmaceutical composition of the present invention can be formulated in accordance with conventional procedures. In the present specification, "non-orally" include subcutaneous injection, intravenous injection, intramuscular injections, intraperitoneal injection or instillation. Injectable preparations, for example, sterile injectable aqueous suspensions or oil suspensions can be prepared by known procedure in the fields concerned, using a suitable dispersant or wetting agent and suspending agent. The sterile injections may be in the state of, for example, a solution or a suspension, which is prepared with a nontoxic diluent administrable non-orally, e.g. an aqueous solution, or with a solvent employable for sterile injection. Examples of usable vehicles or acceptable solvents include water, Ringer's solution and an isotonic aqueous saline solution. Further, a sterile non-volatile oil can usually be employed as solvent or suspending agent. Any non-volatile oil and a fatty acid can be used for this purpose, which includes natural or synthetic or semi-synthetic fatty acid oil or fatty acid, and natural or synthetic or semi-synthetic mono- or di- or tri-glycerides. Rectal suppositories can be prepared by mixing the drug with a suitable non-irritable vehicle, for example, cocoa butter and polyethylene glycol, which is in the solid state at ordinary temperatures, in the liquid state at temperatures in intestinal tubes and melts in rectum to release the drug. As a solid formulation for oral administration, mention is made of powders, granules, tablets, pills and capsules as referred to in the above. In such formulations as exemplified above, the active component compounds can be mixed with at least one additive, for example, sucrose, lactose, cellulose sugar, mannitol,maltitol, dextran, starch, agar, alginates, chitins, chitosans, pectins, tragacanth gum, gum arabic, gelatins, collagens, casein, albumin, synthetic or semi-synthetic polymers or glycerides. These formulations can contain, as in conventional cases, further additives, for example, an inactive diluent, a lubricant such as magnesium stearate, a preservative such as paraben or sorbic acid, an anti-oxidant such as ascorbic acid, α-tocopherol or cysteine, a disintegrator, a binder, a thickening agent, a buffer, a sweetener, a flavoring agent and a perfuming agent. Tablets and pills can further be prepared with enteric coating. Examples of liquid preparations for oral administration include pharmaceutically acceptable emulsions, syrups, elixirs, suspensions and solutions, which may contain an inactive diluent, for example, water, which is conventionally employed in the field concerned. The pharmaceutical composition of this invention is less toxic, and is used as a medicine for animals, especially mammals (e.g. human being, dog, rabbit, mouse, etc.). The pharmaceutical composition of this invention is formulated by combining (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5yl) biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a salt thereof with manidipine hydrochloride. This composition serves to decrease the dosages of the individual effective components, and, as a result, suppresses undesirable side effects observed in the case of administering the respective compounds singly. The dose of a specific patient is dependent on the age, body weight, general health conditions, sex, diet, dose interval, administration routes, excretion rate, combinations of drugs and conditions of the diseases treated, while taking these and other necessary factors into consideration. Typical daily doses of the composition are within the range of from 1/50 of the minimal recommendable clinical dose to maximal recommendable dose in the case of practical administration of the compounds individually. For example, (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5yl) biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate to be administered at a dose of 0.01 to 150 mg/patient/day can be administered at a dose of 0.0002 to 150 mg/patient/day, preferably 0.001 to 60 mg/patient/day, more preferably 0.01 to 20 mg/patient/day by combining it with a daily dose 2 to 20 mg of manidipine hydrochloride. Needless to say, while these dosage ranges can be adjusted by a necessary unit base for dividing a daily dose, as described above, such doses are decided depending on the diseases to be treated, conditions of such diseases, the age, body weight, general health conditions, sex, diet of the patient then treated, dose intervals, administration routes, excretion rate, and combinations of drugs, while taking these and other necessary factors into consideration. The desired unit dose of the composition of this invention is administered once or twice daily (preferably once). For example, the unit dose composition contains 0.0002 to 150 mg, preferably 0.001 to 60 mg, more preferably 0.01 to 20 mg of (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5yl) biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate by combining with 2 to 20 mg of manidipine hydrochloride By the following test examples and working examples, the present invention will be illustrated in more detail. The physiological activities of the composition comprising (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5yl) biphenyl-4-yl] imidazole-7-carboxylate or a salt thereof and manidipine hydrochloride are described by the following test examples. Test Example 1 Antihypertensive activity in spontaneously hypertensive rats (SHR) by the co-administration with a calcium antagonistic drug Compound 1: (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-I-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate MDP: manidipine Method: Male SHR of 20 week old were divided into six groups (five animals per group). The respective groups were administered orally with the compound 1 (0.1 or 1 mg/kg, p.o.) or MDP (3-mg/kg, p.o.) alone or with a mixture of them once a day for two weeks. On the first, 7th and 14th day at 5 hr after the administration, blood pressure of each test animal was measured by the tail cuff method under unanesthesia. Results: As shown in Table 1. Single administration of MDP (3 mg/kg/day, p.o.) showed apparent antihypertensive effect, and the compound 1 (0.1 and 1 mg/kg/day) performed dose dependent antihypertensive effect. The antihypertensive activity of the compound 1 was enhanced by the co-administration with MDP (3 mg/kg/day). The hypotensive activity observed by the co-administration of the compound 1 (0.1 mg/kg) with MDP was stronger or substantially the same as that observed by administering the compound 1 alone (1 mg/kg). This result shows that simultaneous usage of both drugs can decrease in the dosages of the respective drugs. Antihypertensive activity by the combination of compound 1 and MDP drug in spontaneously hypertensive rats Test group (dosage) mg/kg/day,p.o. Before admin. 1 day (blood 1 week pressure : 2 weeks mmHg) Control - 188 ± 3 184 ± 2 181 ± 3 179 ± 1 MDP (3) 190 ± 5 157 ± 2 132 ± 5 136 ± 7 Cpd. 1 (0.1) 190 ± 2 157 ± 2 158 ± 4 160 ± 4 Cpd. 1 (1) 196 ± 3 148 ± 3 131 ±13 142 ± 4 MDP(3)+Cpd.1 (0.1) 193 ±4 4 130 ± 6 128 ± 6 141 ± 5 MDP(3)+Cpd.1 (1) 192 ± 3 127 ± 4 114 ± 4 111 ± 3 Numerical values: average values ± standard error As is apparent from this test example, the composition comprising (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5yl) biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a salt thereof and manidipine hydrochloride manidipine hydrochloride enhances the action of the respective drug administered singly and can decrease the dosages of the respective drugs. As a result, suppression of the occurrence of undesirable side effects observed when these drugs are administered singly can be expected to a considerable extent. Working Example Formulation Examples The pharmaceutical composition formulated by combination of (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5yl) biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a salt thereof and manidipine hydrochloride , can be prepared by the prescriptions described as follows. 1 . Capsules (1) (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate 2 mg (2) manidipine hydrochloride 2 mg (3) lactose 96 mg (4) microcrystalline cellulose 70 mg (5) magnesium stearate 10 mg one capsule 180 mg (1), (2), (3), (4) and 1/2 of (5) were mixed and then granulated. To the granules was added the remainder of (5), and the whole was filled into a gelatine capsule. 2. Tablets (1) (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate 2 mg (2) manidipine hydrochloride 2 mg (3) lactose 93.4 mg (4) corn starch 20 mg (5) polyethylene glycol 2.6 mg (6) hydroxypropyl cellulose 4 mg (7) carmellose calcium 5.6 mg (8) magnesium stearate 0.4 mg one tablet 130 mg (1), (2), (3), (4), (5), 2/3 of (6), 2/3 of (7) and 1/2 of (8) were mixed and then granulated. To the granules were added the remainders of (6), (7) and (8), followed by subjecting the mixture to compression molding.

Claims: Use of a combination of (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a pharmaceutically acceptable salt thereof with manidipine hydrochloride for the manufacture of a medicament for the prophylactic or therapeutic treatment of hypertension. A pharmaceutical composition for the treatment of hypertension, which comprises (±)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylate or a pharmaceutically acceptable salt thereof in combination with manidipine hydrochloride.

Inventors: INADA YOSHIYUKI, KUBO KEIJI, INADA, YOSHIYUKI, KUBO, KEIJI
Applicants: TAKEDA PHARMACEUTICAL, TAKEDA PHARMACEUTICAL COMPANY LIMITED
Application year: 1994
Main classification: A61K31
IPC codes: A61P9, A61K31, A61K45